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This letter presents studies of several simple integrated circuits—n-channel metal-oxide semiconductor inverters, five-stage ring oscillators, and differential amplifiers—formed on thin, bendable plastic substrates with printed ribbons of ultrathin single-crystalline silicon as the semiconductor. The inverters exhibit gains as high as 2.5, the ring oscillators operate with oscillation frequencies between 8 and 9MHz at low supply voltages (∼4V), and the differential amplifiers show good performance and voltage gains of 1.3 for 500mV input signals. The responses of these systems to bending-induced strains show that relatively moderate changes of individual transistors can be significant for the operation of circuits that incorporate many transistors.

Dip Pen Nanolithography (DPN TM) is an important technique for nanotechnology and a fundamental new tool for studying the consequences of miniaturization. In this scanning probe technique a sharp tip is coated with a functional molecule (the 'ink') then brought into contact with a surface where it deposits ink via a water meniscus. The DPN process is a direct-write pattern transfer technique with nanometer resolution and is inherently general with respect to usable inks and substrates, including biomolecules such as proteins and oligonucleotides. We present functional extensions of the basic DPN process by showing multiple active probes along with the ability to load different inks onto probe tips. We present the fabrication process and characterization of thermomechanically actuated probes that use the bimorph effect to induce deflection of individual cantilevers as well as the integration of these probes with control electronics and an interface module. As an additional improvement to DPN functionality, we developed the capability to write with different inks on the probe array, permitting the fabrication of multicomponent nanodevices in one writing session. For this purpose, we fabricate passive microfluidic devices and present the microfluidic behavior and ink loading performance of these components.

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